Billionaire Ken Griffin, CEO of Citadel Advisors, oversees the most profitable hedge fund ever. Investors might want to track his trades using quarterly Forms 13F.

In Q2, Griffin sold 9.2 million shares of Nvidia (NVDA 0.78%), cutting his stake by 79%. He also bought 98,752 shares of Super Micro Computer (SMCI -0.68%), increasing his position by 96%. Citadel still invests more in Nvidia, but these trades might indicate changing views.

Nvidia

Nvidia makes graphics processing units (GPUs) that power AI applications and data centers. Analysts claim Nvidia leads AI infrastructure with a 90% market share in AI chips.

Developers favor Nvidia because its GPUs are the fastest and they offer better software tools. Nvidia also provides CPUs and networking equipment that complement its chips. This broad product range helps them outperform competitors.

During Griffin’s selling, Nvidia was valued at around 67 times earnings, which has since decreased as their earnings significantly rose. Wall Street now forecasts 37% annual earnings growth for Nvidia over the next three years, making it a more appealing investment.

Super Micro Computer

Super Micro manufactures servers and complete data center solutions. Their quick innovation keeps them competitive, especially in AI servers.

While competitors like Dell ramp up AI infrastructure production, Supermicro’s expertise in liquid cooling helps them reduce power consumption significantly.

Supermicro’s recent financials showed a revenue increase of 143% but a decline in gross margin. There are concerns about pricing power due to rising competition.

Griffin bought Supermicro shares in Q2, but recent allegations of accounting issues may have changed his view. The company is under investigation, echoing past issues that led to a significant fine in 2020.

Despite the challenges, AI server sales are expected to grow 30% annually. Analysts project Supermicro’s earnings to rise 54% in the next year, suggesting a potentially attractive valuation. However, regulatory concerns may lead Griffin to reduce his stake in Supermicro.